18-letter words containing o, l, r, s
- optical disc drive — optical disk drive
- optical disk drive — (hardware) (Or "optical disc drive", "optical storage") A generic term for any device that reads and/or writes optical media, i.e. compact discs, DVDs and/or Blu-ray discs or future media that uses light (from a small laser) to read data off a removable, rotating disk. At least one such drive is commonly installed in most personal computers to allow them to play and/or record audio and video media and load and store data such as program installers. The floppy disk has been replaced by optical media due to its vastly greater capacity, e.g. 50,000 megabytes for a dual-layer blu-ray disc compared with 1.5 megabytes for a floppy (over 30,000 times as much).
- optical microscope — traditional magnifying instrument
- optical soundtrack — the final soundtrack on a motion picture, which appears as a band of black and white serrations along a strip of film to the left of the composite print. Light is shined through the serrations and is converted to audible sound.
- order of australia — an order awarded to Australians for outstanding achievement or for service to Australia or to humanity at large; established in 1975
- organic solidarity — social cohesiveness that is based on division of labor and interdependence and is characteristic of complex, industrial societies.
- oriental alabaster — alabaster (def 2).
- oriental cat's-eye — a chatoyant variety of chrysoberyl, used as a gem.
- oriental scops owl — any of a group of small owls having ear tufts and a whistling call, especially Otus scops (Old World scops owl) and O. sunia (Oriental scops owl)
- oriental shorthair — any of a breed of domestic cat, similar to the Siamese but with greenish eyes and often a coat of a solid color
- oscillographically — By means of oscillography.
- overspecialization — excessive specialization, as in a field of study.
- owen stanley range — a mountain range in SE New Guinea. Highest peak: Mount Victoria, 4073 m (13 363 ft)
- pacinian corpuscle — (sometimes lowercase) a microscopic, onionlike body consisting of layers of connective tissue wrapped around a nerve ending, located in the deep layers of skin, tendons, etc., and functioning as a sensory receptor of pressure and vibration.
- pair of spectacles — a score of 0 in each innings of a match
- parallel processor — (parallel) A computer with more than one central processing unit, used for parallel processing.
- parallel resonance — the resonance that results when circuit elements are connected with their inductance and capacitance in parallel, so that the impedance of the combination rises to a maximum at the resonant frequency
- parathyroid glands — any of several small oval glands usually lying near or embedded in the thyroid gland.
- passive vocabulary — all the words, collectively, that a person can understand
- pectoral sandpiper — an American sandpiper, Calidris melanotos, the male of which, when courting, inflates its chest conspicuously.
- pellitory of spain — a small Mediterranean plant, Anacyclus pyrethrum, the root of which contains an oil formerly used to relieve toothache: family Asteraceae (composites)
- people's democracy — (in Communist ideology) a country or form of government in transition from bourgeois democracy to socialism. In this stage there is more than one class, the largest being the proletariat, led by the Communist Party, which is therefore the dominant power
- percussion flaking — a method of forming a flint tool by striking flakes from a stone core with another stone or a piece of bone or wood.
- percussion welding — a form of resistance welding in which the required pressure is provided by a hammerlike blow.
- personal allowance — the amount of money you are allowed to earn each year without paying tax
- personal assistant — aide
- personal bodyguard — a person employed to protect a particular person
- personal exemption — Your personal exemption is the amount of money that is deducted from your gross income before you have to start paying income tax.
- personal insurance — insurance on personal risk, such as car insurance, health insurance or loss of earnings insurance
- personal organizer — a small notebook with sections for personal information, as dates and addresses.
- pescadores-islands — (used with a plural verb) Penghu.
- phanerocrystalline — (of a rock) having the principal constituents in the form of crystals visible to the naked eye.
- phantasmagorically — having a fantastic or deceptive appearance, as something in a dream or created by the imagination.
- phosphatidylserine — any of a class of phospholipids occurring in biological membranes and fats
- physical geography — the branch of geography concerned with natural features and phenomena of the earth's surface, as landforms, drainage features, climates, soils, and vegetation.
- physical inventory — To carry out a physical inventory is to count all the stock on hand.
- pilgrim's progress — an allegory (1678) by John Bunyan.
- pilotless aircraft — an aircraft equipped for operation by radio or by robot control, without a human pilot aboard; drone.
- plains grasshopper — a large, destructive short-horned grasshopper, Brachystola magna, of the western U.S., marked by pinkish hind wings.
- plight one's troth — to make a promise of marriage
- political prisoner — sb imprisoned for political dissidence
- polynesian tattler — a sandpiper, H. incanus, native to the Pacific coastal regions
- polystyrene cement — a purpose-made adhesive for fixing rigid polystyrene
- population figures — population totals; statistics relating to the size of populations
- positively charged — having a positive charge
- post-revolutionary — of, pertaining to, characterized by, or of the nature of a revolution, or a sudden, complete, or marked change: a revolutionary junta.
- postal storage car — a railroad car for transporting unsorted mail.
- postmaster general — the executive head of the postal system of a country.
- postmillenarianism — postmillennialism.
- postviral syndrome — debilitating condition occurring as a sequel to viral illness